The BRB determined the amino acid sequence of about 600 samples. About 250 of these analyses were for unknown proteins or peptides, and the remainder were for quality control of synthetic peptides. Most of the unknown sequences were determined for endogenous peptides eluted from mouse d and b haplotype molecules (LI, D. Margulies) and from human HLA-A3, -A2 and -B27 (BRB). From these analyses, amino acid residues in peptides requisite for peptide binding to particular class I molecules have been determined. This information allows one to search protein sequence databanks for potential antigenic T cell epitopes that are recognized by cytotoxic T lymphocytes which has important implications for vaccine development. In addition, proteins from a large variety of other sources have been sequenced in the facility. These include a 28kd coat protein from P. gallinae and the 25 Kd ookinetic surface antigen from P. falciparum (Kaslow, LMR); vaccinia proteins (Moss, LVD); dengue viral proteins (Lai, LID); various glycosidases from C. albicans (Williamson, LCI); Il-2 precursor fragment (Kaliner, LCI); eosinophil proteins (Rosenberg, LHD); Duffy blood group antigen (Miller, LMR); TGF~ (Sporn, NCI); and tumor associated antigens (Seon, Roswell Park Memorial Inst.). Endothelins in primary rat astrocytes were shown to be subject to selective autoregulation, as demonstrated by the potentiation of endothelin-1 secretion after activation of glial endothelin receptors.